I remember when computers would be able to speak/understand natural language – it was just around the corner in the ’60s. And since then it has faded further into the future with each new attempt to solve the problem. A recent Scientific American Mind blog post by Ben Thomas gives a similar forecast for brain connectivity. (here) It is an interesting piece on how something can be too optimistic but still worth trying to do.
Here are a few random bits from the post on the subject of models and metaphors of the brain:
In 1956, a legion of famed scientific mindsdescended on Dartmouth College to debate one of mankind’s most persistent questions: Is it possible to build a machine that thinks? The researchers had plenty to talk about – biologists and mathematicians had suggested since the 1940s that nerve cells probably served as binary logic gates, much like transistors in computer mainframes. Meanwhile, computer theorists like Alan Turing and Claude Shannon had been arguing for years that intelligence and learning could – at least in theory – be programmed into a machine of sufficient complexity. Within the next few decades, many researchers predicted, we’d be building machines capable of conscious thought. Fifty-odd years after that first Dartmouth Conference, our sharpest supercomputers still struggle to hold basic conversations. … The more we learn about how the brain works, the more interwoven and inextricable we realize its components and processes are – and the less like a computer it seems.
Twenty years ago, researchers compared the brain to a supercomputer packed with billions of microchips. At the turn of the twentieth century, it was a great steam engine; a hundred years before that, an intricate piece of clockwork. And so on, back through the millennia – until we reach the ancient Greeks, who seem to have unleashed this torrent of metaphors by likening the human brain to acatapult (note below). In every age, the brightest scientists and philosophers find themselves tempted to describe the brain in terms of the moment’s latest technology – that is, until new technologies and brain breakthroughs turn those descriptions into clunking relics of bygone eras. … The brain and its workings, in other words, have a way of defying easy classification. Peer inside a neuron and you won’t find any binary switches or churning gears – only an ecosystem of protein structures and neurotransmitter molecules; a sub-cellular country that differs profoundly from any machine built by human hands.
Each metaphor is an improvement. But remember the saying, “What you don’t understand is simple”. We really don’t understand thinking and so it seems a much simpler process than it is. Consciousness is so effortless to us because the way it is produced is hidden from us.
Note: catapult reference is from Science and Language blog (here) :
Because we do not understand the brain very well we are constantly tempted to use the latest technology as a model for trying to understand it. In my childhood we were always assured that the brain was a telephone switchboard. (‘What else could it be?’) I was amused to see that Sherrington, the great British neuroscientist, thought that the brain worked like a telegraph system. Freud often compared the brain to hydraulic and electro-magnetic systems. Leibniz compared it to a mill, and I am told some of the ancient Greeks thought the brain functions like a catapult. At present, obviously, the metaphor is the digital computer.” (John R Searle, or so the Internet says.)